Ruminant adipose tissue (AT) stores lipids for use in productive functions during negative energy balance (NEB) which occurs during early lactation or undernutrition. The molecular mechanisms underlying the nutritional regulation of gene expression in AT from lactating goats are not fully understood. The expression of more than 60% of protein-coding genes is post-transcriptionally regulated by microRNAs (small non-coding RNAs, 18 to 25 nucleotides). The objective of our study was to investigate the effects of NEB obtained by underfeeding on the miRNA profile (miRNome). Using RNA-sequencing, we compared the AT miRNome of 5 goats fed a standard diet ad libitum to that of 6 goats food deprived (FD_d) for 48 h. We identified 637 known miRNAs in omental AT and 16 of them presented an expression modulated by food deprivation (FD). Functional analyses of the predicted protein-coding target genes of the 16 differentially expressed miRNAs revealed significant enrichment in genes involved in cell life including apoptosis, cell proliferation, and differentiation as well as gene expression machinery. These data suggest that miRNAs may play a key role in the regulation of AT remodeling. Two major miRNAs, miR-223-3p and miR-21-5p, which were upregulated by FD suggested increased AT inflammation.

Read the full article in the Journal of Animal Science.